def ReceiveRstPacketOn(self, netid):
# self.last_packet is the last packet we received. Invert direction twice.
_, ack = packets.ACK(self.version, self.myaddr, self.remoteaddr,
self.last_packet)
desc, rst = packets.RST(self.version, self.remoteaddr, self.myaddr,
ack)
super(TcpBaseTest, self).ReceivePacketOn(netid, rst)
def SendRSTOnClosedSocket(self, version, netid, expect_rst):
self.IncomingConnection(version, tcp_test.TCP_ESTABLISHED, netid)
self.accepted.setsockopt(net_test.SOL_TCP, net_test.TCP_LINGER2, -1)
net_test.EnableFinWait(self.accepted)
self.accepted.shutdown(SHUT_WR)
desc, fin = self.FinPacket()
self.ExpectPacketOn(netid, "Closing FIN_WAIT1 socket", fin)
finversion = 4 if version == 5 else version
desc, finack = packets.ACK(finversion, self.remoteaddr, self.myaddr,
fin)
self.ReceivePacketOn(netid, finack)
try:
self.ExpectPacketOn(netid, "Closing FIN_WAIT1 socket", fin)
except AssertionError:
pass
self.accepted.close()
desc, rst = packets.RST(version, self.myaddr, self.remoteaddr,
self.last_packet)
if expect_rst:
msg = "closing socket with linger2, expecting %s: " % desc
self.ExpectPacketOn(netid, msg, rst)
else:
msg = "closing socket with linger2, expecting no packets"
self.ExpectNoPacketsOn(netid, msg)
def RstPacket(self):
return packets.RST(self.version, self.myaddr, self.remoteaddr,
self.last_packet)
def CheckConnectOption(self, version):
ip_layer = {4: scapy.IP, 6: scapy.IPv6}[version]
netid = self.RandomNetid()
s = self.TFOClientSocket(version, netid)
self.clearTcpMetrics(version, netid)
# Connect the first time.
remoteaddr = self.GetRemoteAddress(version)
with self.assertRaisesErrno(EINPROGRESS):
s.connect((remoteaddr, 53))
self.assertSocketNotConnected(s)
# Expect a SYN handshake with an empty TFO option.
myaddr = self.MyAddress(version, netid)
port = s.getsockname()[1]
self.assertNotEqual(0, port)
desc, syn = packets.SYN(53,
version,
myaddr,
remoteaddr,
port,
seq=None)
syn.getlayer("TCP").options = [(TCPOPT_FASTOPEN, "")]
msg = "Fastopen connect: expected %s" % desc
syn = self.ExpectPacketOn(netid, msg, syn)
syn = ip_layer(str(syn))
# Receive a SYN+ACK with a TFO cookie and expect the connection to proceed
# as normal.
desc, synack = packets.SYNACK(version, remoteaddr, myaddr, syn)
synack.getlayer("TCP").options = [(TCPOPT_FASTOPEN, "helloT"),
("NOP", None), ("NOP", None)]
self.ReceivePacketOn(netid, synack)
synack = ip_layer(str(synack))
desc, ack = packets.ACK(version, myaddr, remoteaddr, synack)
msg = "First connect: got SYN+ACK, expected %s" % desc
self.ExpectPacketOn(netid, msg, ack)
self.assertSocketConnected(s)
s.close()
desc, rst = packets.RST(version, myaddr, remoteaddr, synack)
msg = "Closing client socket, expecting %s" % desc
self.ExpectPacketOn(netid, msg, rst)
# Connect to the same destination again. Expect the connect to succeed
# without sending a SYN packet.
s = self.TFOClientSocket(version, netid)
s.connect((remoteaddr, 53))
self.assertSocketNotConnected(s)
self.ExpectNoPacketsOn(netid,
"Second TFO connect, expected no packets")
# Issue a write and expect a SYN with data.
port = s.getsockname()[1]
s.send(net_test.UDP_PAYLOAD)
desc, syn = packets.SYN(53,
version,
myaddr,
remoteaddr,
port,
seq=None)
t = syn.getlayer(scapy.TCP)
t.options = [(TCPOPT_FASTOPEN, "helloT"), ("NOP", None), ("NOP", None)]
t.payload = scapy.Raw(net_test.UDP_PAYLOAD)
msg = "TFO write, expected %s" % desc
self.ExpectPacketOn(netid, msg, syn)